Process for finishing automobile bodies



Patented May 26, 1925.

lessen CHARLES WIDMAN, or DETROIT, 'MICHIGANa PROCESS FOR FINISHING ILU'IOMOBILE BODIES.

No Drawing.

To all whom it may COW/067%.

Be it known that I, CHARLES H. WIDMAN, a citizen of the United States, and resident of the city of Detroit, county of WVayne, and State of Michigan, have invented cer tain new and useful Improvements in a Process for Finishing Automobile Bodies, of which the following is a specification.

In the manufacture of automobile bodies, until recent months, it has been customary to finish them by either one of two methods. That is to say, the bodies were either painted after assembly, in which case a wooden frame was utilized, or were enameled after assembly, in which case a metal frame was utilized.

My United States Letters Patent No. 1,507,551, issued on September 2nd, 1924, describes yet another method wherein the various pieces forming the casing of the body are first formed then enameled, or otherwise coated and then assembled to a wooden frame. 7

Recently a new product for coatingautomobile bodies has met with some favor among automobile manufacturers. This coating is commercially known as Duco. Duco coatings include a base of cotton and certain other ingredients such as cellulose, alcohol, etc., and may be said to belong to the general class of finishes known as pyroxylin finishes.

he customary manner of using Duco is to first provide the assembled body casing with an iron oxide prime coat and then with several coatings of Duco. The Duco finish has the property of rapid drying and after drying is very hard and highly resists removal or marring.

Certain difiiculties have been encountered, however, in the use of Duco finish for the reason that in such use it has been found absolutely necessary to thoroughly clean every particle of rust from the metal before applying the priming coats. It has been found also that the priming coats must be absolutely dry with all oxides removed before the Duco coating is applied.

Much difiiculty has been encountered in removing all of the rust from the assembled body casing and much time is required to thoroughly dry the prime or under-coating. Oftentimes it is impossible to readily ascer tain whether or not all of the oxides have been removed from the prime or under- Application filed September 26, 1324. Serial No. 740,017.

coatings withthe result that the .Duco finish is applied before this has been done and poor results are obtained.

Following the broad principles set forth and. claimed in my said Letters Patent No.

1,507,551, but more specifically applyingv them to a somewhat different process, I have evolved the process/which consists in first forming the various parts of the body casing, then thoroughly cleaning each individ- PATENT OFFICE. I

ual part to remove all rust (this being easily possible by dipping the various parts in a rust removing compound) then applying the priming or under-coatings to the various pieces, then subjecting such pieces to a relatively high heat so as to thoroughly dry the under-coatings and bake them on the metal, then assemble the various pieces to the frame and then apply a finishing coating of Duco or the like. 9 1

In the use of my improved process, I obtain a number of highly beneficial and useful results, among which are the easy and thorough cleaning of the metal; the quick removal of all oils and other oxides from the priming coat by the oxidation thereof due to the high heat to which the parts are subjected; the baking of the priming coat on the metal; and the eflicient coating of the metal after assembly and after the foregoing complete preparations for the finishing coat have been made.

The result of this process is that all of the difficulties heretofore present in using Duco or other final finishes are removed.

I desire it to be understood that my in'r proved process is applicable to final linishes of various, compounds known as,py roxylin finishes or even to paint. 1

I, therefore, desire it to be understood that various finishing coatings may be used and that various other changesma be made in the details of my improved process without departing from the spirit of my inveution,it being my intention to cover by my claims such changes as may be reasonably included within the scope thereof.

What IJclaim is:

1. The process of finishing an automobile body which consists in first forming the val rious portions of the body. casing, then A cleaning the same,then iilacing an undercoating on the same. then assembling the pleces to a frame and'then applying a finishing coating.

2. The process of finishing an automobile body which consists in first forming the various pieces of. the body casing, then cleaning the same, then applying an under-coating to the same, then subjecting the pieces to a relatively high heat, then assembling the pieces to a body frame and then applying a finishing coating to the casing.

3. A process of finishing an automobile body which cOIlSlStS in first forming the various pieces of the body casing, then cleaning the same, then applying an under-coating containing iron oxide to the pieces, then subjecting pieces to a relatively high heat, then assembling pieces: to a body name and then applying a finishing coating to the casin 4. The process of finishing an automobile body consisting of first forming the various portions of the body casing, then cleaning the same, then applying an under-coating to the, pieces, then assembling the pieces to a body frame and then applying a finishing coating of n pyroxylin finish.

5. The process of finishing an automobile body Which consists in first forming the various pieces of the body casing, then cleaning the same, then applying an undercoating to the same, then subjecting the pieces to a relatively high heat, then assembling the pieces to a body frame and then applying a finishing coating, of a pyi-oxylin finish.

6. A process of finishing an automobile body which consists in first, forming the various pieces of the body casing, then cleaning the same, then applying an under-coating containing iron oxide to the pieces, then subjecting pieces to a relatively high heat, then assembling pieces to a body frame and then applying a finishing coating, of a pyroxylin finish.

CHARLES H. \VIDMAN. 

